I sent mine back to get re-programed it made a big differance. If I remember right it took less than a week to get it back. There is no charge. It also helps to use 87 octane.....

 

I heard it all the stereo weight you added. Dump the thump. :winker:

 

yes, my sunsation 288 suffered from that. Dustin Whipple at Whipple or Arizona Speed can reprogram it.

 

couple guys I know had the soot problem and they were running top octane gas .......

.....and the problem was solved, as hot4rd stated, by using the lower octane gas recommended in the manual.

What Octane are you using? Might be a simple fix.

 

I have a few friends who had the same problem. Turns out there was a "soft recall" form Mercury on the ECMs. Bring it to your dealer and he should have it done under warranty.

 

Yep. Had the problem on my 288 but a warrantied ECU change fixed it. Basically the orignal motors were set to run a little too rich causing soot build up in no-wake zones.

 

I still get a lot of soot on my 05,,, the rub rail won't come clean anymore..

 

Yep a warrantied ECU change fixed it. Basically the orignal motors were set to run a little too rich causing soot build up in no-wake zones.

Same here. See if Merc will replace your ECU.

 

I still get a lot of soot on my 05,,, the rub rail won't come clean anymore..

How many hours?

 

MAYBE IF YOU DO A SEARCH YOU WILL FIND I POSTED THAT SAME PROBLEM. I TRIED MERCURY FIRST,NOT MUCH HELP [MAYBE MY LOCAL DEALER]. THEN I SPENT $1200 WITH DUSTIN @ WHIPPLE,NOT MUCH DIFFERENCE AT ALL. SAVE YOUR MONEY.FINALLY THE SECOND TRY WITH MERCURY THEY ADMITTED THERE WAS A PROBLEM AND SENT ME A BRAND NEW COMPUTER [NOT RE-PROGRAMED]. THAT TOOK CARE OF 80% OF MY SOOT PROBLEM. GET A NEW COMPUTER FROM MERC. P.S. SCRUBBING BUBBLES WILL REMOVE THE SOOT VERY EASY... "THEY DO THE SCRUBBING SO YOU DONT HAVE TO"

 

I heard to use 87 octane also, that mercury has the motors programmed to run rich for longevity and that 87 helps w/ the soot, my buddy w/ a 2000 288 sunny w/ 502 said it helpd w/ his problem

 

Yes use 87. It is recomended in the manual for that motor as well. You WILL see less soot. I keep a nice wax on the boat and when I pull out at the end of the day I can take a wet towel and soot comes off 100%.

 

if i use anything but 87 oc,i get it bad (500hp)

 

Merc still has this problem, and BAD!!! I am running 87 Octane, so that does not cure the problem. What makes it even worse for me, since my transom squats so much at idle, the soot gets trapped under the platform. I guess I will be calling Monday for a new ECU.

 

Try Merc and see what they say, but my 575 cleared up a buch at 25 hours. It was the ECU recognizing that the motor had enough hours to have been broken in OR, at the same time I changed oil to Penzoil 20-40. It may have been that the oil helped the engine seat the moving parts and it stopped. When I say stopped-it was immediate and I could run 5-6 hours and barely see any soot or film. It was a MAJOR difference. Just not sure why.

 

Try Merc and see what they say, but my 575 cleared up a buch at 25 hours. It was the ECU recognizing that the motor had enough hours to have been broken in OR, at the same time I changed oil to Penzoil 20-40. It may have been that the oil helped the engine seat the moving parts and it stopped. When I say stopped-it was immediate and I could run 5-6 hours and barely see any soot or film. It was a MAJOR difference. Just not sure why.

Good idea, I will check with Merc and change the oil and see what happens! I will be putting in Royal Purple...

 

Got your message Gilla...